Giuseppe Mangiacavallo appears in Season 5 Episode 23: The Mangiavallo Curse Makes a Lousy Wedding Present.
He is a man who is in his 80s. He has white and grey hair, white eyebrows, and a white moustache. He has broad shoulders and he is much taller than Sophia.
When Sophia was 14 in Sicily, her father arranged for her to marry the neighbour's son, Giuseppe Mangiacavallo. Her dowry was 2 chickens, a ladle, and a goat. He jilted Sophia at the altar, when he left for America on a cattle boat without her. He is considered one of Sophia's husbands.
Sophia spits when she says his name.
The night he left her at the altar, Sophia cursed him with the following:
"Giuseppe Mangiacavallo, from this day forward may you and all your future generations never know true love.
May you be sterile and may all your offspring be sterile.
May your hair never lie flat and may your socks always slip down inside your shoes."
He is the grandfather of the groom at Dorothy's goddaughter's wedding and it seems the curse did not work as Dorothy reveals that he is in his 80s, is a multi-millionaire, and enjoys perfect health. Sophia says it's a very slow-acting curse that has lulled Giuseppe into a false sense of security.
Sophia and Giuseppe meet at the wedding. Giuseppe compliments Sophia's beauty. When she reveals that she put a curse on him, he laughs it off and says that that was a thousand miles and a hundred years ago. As he walks away, he pulls up his socks which indicates that part of the curse has already come true. Sophia looks satisfied.
Later, Giuseppe invites Sophia to dance with him but Sophia says it's too late for him and quotes Shakespeare, saying: "A plague on both your houses" but Giuseppe responds by saying "actually, I have four houses and a summer home." Dorothy tries to get Sophia to calm down and says there is no curse, but at that exact moment the bride storms off and says she hates the groom.
Giuseppe tries to calm things down, saying it's just a little lover's quarrel and encouraging the guests to enjoy the party before leaving to see what's wrong. As he leaves, he pulls up his socks again and Sophia looks satisfied with herself and says it was worth the wait to see the Mangiavallo curse finally coming to fruition.
He comes back and tells Sophia that Joey (the groom) is alone in the bridal suite, the bride is who-knows-where, and the band doesn't even know Volare. He says she has got to do something about the curse. Sophia asks why she should help him when he left her at the altar, which dishonoured her and her father, He responds that he was a kid and he was scared that if he got married and had a family he'd never get out of the village where they grew up and that leaving Sophia was the toughest thing he ever did.
Sophia insists that he say the following to everyone at the wedding: "This is Sophia Petrillo, the girl who stood me up at the altar 70 years ago. And I just asked her to be my wife again and again she said no. And so, from now on, I'm gay." and he says it, so Sophia declares that they're even.
They go to remove the curse on the bride and groom, but find that they have already made up. Sophia says that the curse is over.
They dance together and Giuseppe reminisces about a restaurant in Sicily that they'd go to on Sundays. Giuseppe would save all week to go there and split a plate of pasta with Sophia. Sophia doesn't remember, but (correctly) guesses that the place had red checkered tablecloths, chianti bottles, and bad paintings of the Colluseum.